Recently, blood pressure monitors have come into wide use not only in, for example, hospitals but also in general households for the purpose of health care. The blood pressure monitors for the general households are typically automatic blood pressure monitors which are easy to operate.
Automatic blood pressure monitors based on various measurement methods and configurations have been developed, and an oscillometric electronic blood pressure monitor is one such blood pressure monitor. This oscillometric electronic blood pressure monitor detects a pulse wave superposed on the inner pressure of a fluid bag (generally called “air bag” since air is used), and calculates a blood pressure on the basis of changes in the amplitude of the pulse wave. This oscillometric electronic blood pressure monitor includes a body compressor (generally called a cuff) which is wound around the upper arm and has an air bag, a pressure sensor, a pump and an exhaust valve which are in communication with the air bag through a tube, an information processing unit which is connected to the pressure sensor, the pump and the exhaust valve, and an operation switch and a display which are connected to the information processing unit.